INTERACTION OF EXERCISE TRAINING AND CHRONIC ETHANOL INGESTION ON HEPATIC AND PLASMA ANTIOXIDANT SYSTEM IN RAT

This study was undertaken in order to investigate the interactive effe cts of exercise training and chronic ethanol consumption on the antiox idant system in rat liver and plasma. Fisher-344 rats were treated in separate groups as follows: sedentary control (SC); exercise training (ET) for 6.5 weeks; ethanol 20% (2.0 g kg(-1), p.o.) for 6.5 weeks; an d ET and ethanol administration In liver, ET significantly decreased t he malondialdehyde (MDA) level (73% of SC). Chronic ethanol significan tly increased catalase (CAT) activity and MDA levels (126% and 135% of SC), respectively, and also depleted the reduced glutathione (GSH) le vel and the reduced to oxidized glutathione (GSH/GSSG) ratio (81% and 38% of SC), respectively. Exercise training plus ethanol significantly increased CAT and glutathione reductase (GR) activity (126% and 118% of SC), respectively, and decreased the MDA level (67% of SC). In plas ma, ethanol significantly enhanced CAT activity and MDA levels (173% a nd 221% of SC), respectively. Ethanol ingestion also increased the CAT /superoxide dismutase (SOD) ratio (216% of SC) in plasma, Training plu s ethanol ingestion significantly increased CAT activity and MDA level s (208% and 148% of SC), respectively, and increased CAT/SOD and gluta thione peroxidase (GSH-Px)/SOD ratios (279% and 142% of SC), respectiv ely. The data indicate that the combination of exercise and ethanol in gestion resulted in an enhanced hepatic CAT and GR activity to elimina te H2O2 and to maintain endogenous GSH levels. Thus, training ameliora ted the ethanol-induced oxidative injury in the liver. The ratio of CA T/SOD in plasma increased twofold due to chronic ethanol intake and th reefold due to the combination, which may be used as an index of oxida tive stress. (C) 1997 by John Wiley & Sons, Ltd.